In recent years, so-called positional services are becoming widespread. In the positional services, positional information of a mobile terminal apparatus is obtained using the Global Positioning System (GPS), a wireless local area network (WLAN), a baseband, and so on, and services depending on a position of the mobile terminal apparatus are provided.
Under the above-described circumstances, power consumption for positioning a mobile terminal apparatus (hereinafter referred to as a positioning power) is increasing. In particular, in the GPS, a bit rate of GPS signals from satellites is low (50 bps), and it takes about 30 minutes for receiving a GPS signal frame (1500 bits). Accordingly, compared with power consumption for obtaining state information of a mobile terminal apparatus by, for example, an acceleration, the number of steps, and so on, positioning power at the time of using GPS increases drastically. Also, in a WLAN and a baseband, a Basic Service Set Identifier (BSSID) and a cell-ID, which are obtained by a mobile terminal apparatus, have to be transmitted to a server, and thus compared with power consumption for obtaining state information of a mobile terminal apparatus, for example, an acceleration, the number of steps, and so on, positioning power increases drastically. Accordingly, it becomes important to reduce power consumption for positioning the mobile terminal apparatus.
For a mechanism to reduce power consumption, a control technique of a mobile terminal apparatus has been proposed in which, for example, a determination (hereinafter referred to as a “movement determination”) is made of whether the mobile terminal apparatus has moved or not using sensors installed on the mobile terminal apparatus, and if the mobile terminal apparatus has not been moved, positioning is not carried out, and the positional information already obtained is used.
In the above control technique, a sensor consumes power for movement determination, but positioning power, which is greater than power consumption for movement determination, is reduced, and thus it is possible to suppress power consumption of the mobile terminal apparatus as a result.
Related-art techniques have been disclosed in Japanese Laid-open Patent Publication Nos. 2011-149860, 2000-352519, and 2011-022115.